A light emitting diode (LED) refers to a sort of semiconductor device capable of displaying light of different colors by forming a PN diode of a compound semiconductor as a light source. The LED has advantages of long life, small size and weight, and low-voltage operation. Furthermore, the LED is resistant against impact and vibration, does not need a warm-up time and complex driving, can be packaged after being mounted on a substrate or lead frame in different forms, and thus may be modularized for various purposes to be applied to a backlight unit or various lighting devices.